Knight Farm Machinery trailed sprayers: Some six years ago we took a look at buying a pre-owned Knight trailed sprayer, concluding that even the earliest examples were a sound used purchase. Time has moved on, so it’s now perhaps better to consider machines that are a bit younger. The key point, however, is that even 10-year-old Knight models can still be updated to a spec that should match most of today’s user needs, as James de Havilland discovers